下伏土洞加筋地基条形荷载下应力扩散计算  

Calculation of stress distribution of reinforced foundation in underlying soil caves under strip load

作　　者：周宏伟 秦礼友 叶世集 林上顺 ZHOU Hongwei;QIN Liyou;YE Shiji;LIN Shangshun(3th Engineering Co.,Ltd.of China Railway No.2 Engineering Group,Chengdu 610000,China;School of Civil Engineering,Fujian University of Technology,Fuzhou 350118,China)

机构地区：[1]中国中铁二局第三工程有限公司,四川成都610000 [2]福建工程学院土木工程学院,福建福州350118

出　　处：《福建工程学院学报》2019年第6期524-531,共8页Journal of Fujian University of Technology

摘　　要：通过大变形有限元分析,对下伏土洞加筋地基条形荷载下应力扩散的作用机理和沉降进行研究,分析了条形基础置于土体上的土体附加应力扩散、土洞区内应力及沉降变化规律。结果表明,土洞区内出现应力集中,下伏土洞地基沉降主要是由于土洞区内软弱土体变形造成。加筋体会增强应力扩散从而减小沉降,加筋体长度和埋深均存在最佳值;多层加筋较单层加筋更利于应力扩散,且层间会出现未完全拱形应力集中区域;相同加筋范围,层数增大对应力扩散影响较小;增大加筋范围更有助于应力扩散。Through finite element analysis of large deformation, the mechanism and settlement of stress distribution of the reinforced foundation in underlying soil caves under the strip load were studied;the additional stress diffusion of soil body, and the variation of stress and settlement in the soil cave were analyzed. Results show that stress concentration occurs in the soil cave, and the settlement of the underlying soil cave foundation is mainly caused by the deformation of the weak soil in the soil cave area. The reinforcement will enhance the stress diffusion and reduce the settlement, with optimum values for both reinforcement length and depth. Multi-layer reinforcement is more conducive to stress diffusion than single-layer reinforcement, and there is an area of incomplete arch stress concentration between the layers. In the same reinforced range, the increase in the number of layers has little influence on the stress diffusion, and the increase of the reinforced range is more conducive to stress diffusion.

关 键 词：应力扩散 土洞 条形荷载 土拱 

分 类 号：TU431[建筑科学—岩土工程]